IBM

IBM Watson Natural Language Understanding

Analyze text to extract metadata from content such as concepts, entities, keywords, categories, sentiment, emotion, relations, and semantic roles.

Documentation GitHub

Documentation

https://cloud.ibm.com/apidocs/natural-language-understanding

Specifications

https://raw.githubusercontent.com/watson-developer-cloud/api-spec/master/natural-language-understanding/natural-language-understanding.json

Other Resources

https://www.ibm.com/cloud/watson-natural-language-understanding/pricing

getting-started

https://cloud.ibm.com/docs/natural-language-understanding

OpenAPI Specification